Essay Title: 

FACS is on the FAST Track to Bacteria Detection in Donor Blood

April 3, 2016 | Author: | Posted in case study, mathematics and economics

FACS is on the FAST Track to Bacteria Detection in Donor Blood

Background of Study

Schmidt and his researchers most recent study , published in Transfusion Medicine , volume 16 , recognizes that screening blood is still extremely important , given the number of transfusions that take place on a daily basis . Detecting bacteria in platelets is the specific problem that this study addresses . Basically , two methods exist to detect bacteria in donated blood . The first method is the culture method . A sample of blood is placed in a culture medium and allowed to incubate . If [banner_entry_middle]

a bacterium grows , then the blood cannot be used . While these samples are accurate , the process occurs so slowly that , in many cases , the blood was already transfuse before the positive result showed . Thus , the process takes too long for it to be use in emergencies and is not deemed clinically efficient . The second method is rapid detection which allows the process to occur more quickly . The Fluorescence-Activated Cell Sorting (FACS ) method provides an opportunity for blood to be tested for bacteria much more quickly than with culture methods

Summary of Study

These researchers sought to use the FACS rapid detection method to isolate six bacteria found often in platelets . These strains are Klebsiella oxytoca , ATCC 13182 Staphylococcus aureus , ATCC 49476 Seratia marcesens , ATCC 43862 Staphylococcus epidermidis , PEI 06-05 Salmonella choleraesuis , ATCC 43971 and Escherichia coli , ATCC 25922 The platelet concentrates (PCs ) were introduced to the inoculated bacteria and stained for easier detection . The PCs and the bacteria strains were treated according to standard protocol for this type of experiement established at the Red Cross Institute in Frankfurt Germany

During analysis , blood samples that had incubated for between five and sixty minutes were deemed to be negative if they had less that 50 fluorescent counts of the bacteria . Samples deemed to be positive had over 100 fluorescent counts of the bacteria . Those that had between 50 and 99 fluorescent counts were allowed to incubate longer and then be retested . The results show that after five minutes of staining , results are comparable to those published in similar studies of varying methods However , after adding a pre-incubation step for the bacteria , the results are more accurate

Justification of the Study

Testing blood for bacteria before using it for transfusions involves two key areas of focus – the analytical sensitivity of the test and the clinical efficiency of the test . The first refers to how accurate the test is , and the second refers to how quickly the results can be obtained . These researchers admit that the analytical sensitivity for FACS is lower than that of culture sample methods . However , the time it takes to get results from a culture sample may be prohibitive . For example , in a recent test , 113 of 184 platelet concentrates were already placed into the recipient before the samples were found to be positive for bacteria . The testing time was seven days in this case (Te Boekhorst , et al , 2005 . That is a very long time , particularly if… [banner_entry_footer]


This author has published 9453 articles so far. More info about the author is coming soon.
Did you like this essay sample?

You must be logged in to post a comment.